Well logging instruments are devices configured to move through a wellbore drilled through subsurface rock formations. The devices include one or more tools and other devices that measure various properties of the subsurface formations and/or perform certain mechanical acts on the formations. Such acts include drilling or percussively obtaining samples of the rock formations, and withdrawing samples of connate fluid from the rock formations. Measurements of the properties of the rock formations may be recorded with respect to the instrument axial position (depth) within the wellbore as the instrument is moved along the wellbore. Such recording is referred to as “well logging.”
Well logging instruments can be conveyed along the wellbore by extending and withdrawing an armored electrical cable (“wireline”), to which the instruments are coupled at the end thereof. Extending and withdrawing the wireline may be performed using a winch or similar spooling device. However, such conveyance relies on gravity to move the instruments into the wellbore, which can only be used on substantially vertical wellbores. Wellbores deviating from vertical require additional force to move the well logging instruments through the wellbore.
One conveyance technique for conveying wireline instruments into a non-vertical wellbore includes coupling the wireline instruments to the end of coiled tubing having a wireline disposed therein. The wireline instruments are extended into and withdrawn from the wellbore by extending and retracting the coiled tubing, respectively. However, the use of coiled tubing with wireline instruments is costly and is inherently limited by the amount of pushing force the coiled tubing is capable of providing to assist the movement of the wireline instruments through the wellbore. As a result, the use of coiled tubing is typically problematic in extended reach wells.
Another well logging instrument conveyance technique includes coupling wireline configurable well logging instruments to the end of a drill pipe or similar threadably coupled pipe string. As the pipe string is extended into the wellbore, the wireline is extended by operating a conventional winch while the pipe string is being conveyed into the wellbore. However, this conveyance technique is frequently unreliable as the wireline is positioned in the annulus and subject to crushing, splicing, or other damage. For example, the wireline may become pinched between the drill pipe and the casing or wellbore. Another drawback to using drill pipe to convey the well logging instruments is that the cable disposed outside the pipe disturbs the operation of the sealing equipment and makes it difficult to seal the drill pipe to maintain fluid pressure.
Additionally, the well logging instruments may be positioned at the end of a drill pipe without the use of a wireline cable. In such circumstances, each well logging instrument is provided with a battery and memory to store the acquired data. As a result, the well logging instruments cannot communicate with the surface while downhole. Therefore, the data acquired, that may be critical to efficiently drilling the wellbore, cannot be analyzed at the surface until the wireline instruments return to the surface. Without any communication with the surface, surface operators cannot be certain the instruments are operating correctly and cannot modify the operation of the instruments in view of the data acquired.
Recently, a type of drill pipe has been developed that includes a signal communication channel within the structure of the pipe, which serves to protect the communication channel and assist in the movement thereof. Such drill pipe, known as wired drill pipe (“WDP”), has a signal coupler at each end thereof that is coupled to the signal communication channel within. When the signal coupler of one wired drill pipe is placed in proximity or in contact with the signal coupler of another wired drill pipe, for example when the two pipe ends are coupled together, signals may be transmitted between the signal couplers. These connections provide a contiguous signal communication channel from one end of a series of wired drill pipes to the other. The use of wired drill pipes has provided increased signal telemetry speed for use with “logging while drilling” (“LWD”) instruments over conventional LWD signal telemetry, which typically is performed by mud pressure modulation or by very low frequency electromagnetic signal transmission.
At the surface, while drilling, a surface receiver sub is usually connected to the wired drill pipe (or wired drill string) to receive data from downhole and relay that data to a surface computer system, either by a hard wired connection or wirelessly. When one stand of pipe is drilled, a new stand needs to be connected. To connect a new stand, the surface receiver sub needs to be disconnected from the drill string. With current receiver subs and methods, disconnecting the receiver sub may take several minutes to complete. The same is true when reconnecting the receiver sub onto the newly attached pipe stand. As a result the communications between downhole tools and the surface system is disconnected, usually for at least few minutes, until the new stand is connected to the wired drill string and to the surface receiver sub. During this time, information packets that may have been traveling through the pipe and to the surface receiver sub may be lost.
This process happens in reverse when tripping out of the wellbore. While tripping out, the surface receiver sub is not present and the drill string is lifted out of the wellbore by the elevators and lifting bales. As each stand of drill pipe is tripped out of the wellbore, the rest of the wired drill string is secured on the rig floor by slips while the stand is disconnected from the wired drill string and secured on the rack. The elevators and the lifting bales are then lowered to pickup the next stand. During tripping in the wellbore, there is typically no communication between the downhole tools or other components of the WDP network and the surface system. There must be a receiver communicatively connected to the drill string, near or at the surface, in order to transmit data to the surface system.
As described above, during drilling, the transmission of data is done using a receiver sub that sits below the top-drive which can send the data onwards to the surface system. Since the surface receiver sub is generally threaded to the wired drill string in a top-drive, it is a slow process. The time required to thread in the receiver sub during drilling is acceptable since it takes a significantly longer time to drill a stand as compared to the time to reconnect the receiver sub after communication is disconnected. However, during logging while tripping with “wireline logging” (“WL”) tools using WDP, the tripping time is much faster than the drilling time. Current devices and methods do not afford time to reconnect the receiver sub while tripping the WDP. It is beneficial to have the receiver sub attached to the drill WDP for the maximum amount of time so long as it does not interfere with the attachment of a new pipe stand. Therefore, to effectively use WL instruments with wired drill pipe, an apparatus, system and method for efficiently attaching and detaching a surface receiver sub is needed.